xii VOICE OF MESOPLODOW 369
Ziphioid grooves upon the throat. Nothing is known of the
structure of the internal viscera of this Whale. It appears not
to be really limited to the region of 3STew Zealand, as is often
stated, for Malm has lately described a skull (JBerardius vegae)
from Bering's Straits.1
Mesoplodon2 is a world-wide genus embracing a number of
species ; on the lowest estimate seven, species can be distinguished,
and Sir W. Flower would add two more. These are moderate-
sized "Whales, 15 to 17 feet in length. In the skull the mesethmoid
is ossified ; the nasals are sunk between the upper ends of the
premaxillae. There are but a single pair of teeth in the mandible
attached to nearly the middle of its length (whence the generic
name). The vertebral formula is C 7, D 9 or 10, I, 10 or 11,
Ca 19 or 20. The sternum consists of four or five pieces. The
amount to which the cervical vertebrae are fused varies; but
some are always fused.
The only species which has ever been stranded on the shores
of this country is Ml ~bidens, an example of which -was described
many years ago as the " Toothless Whale of Havre " ; it was an
old animal which had probably lost its teeth. Nevertheless it
received the separate generic and specific name of ^Aodon dalei.
The animal lived for two days out of the water, and made a sound
like the " lowing of a cow/* An instance of the rarity of the
^Whales of this genus is afforded by Jfefl ev/ropaeus, of which only a
single skull is known ; this was extracted from a dead body, found
floating, about the year 1840. It has never appeared since.
M. layardi is remarkable on account of the very large size of its
strap-shaped teeth; these curve over the upper jaw in such a
way as to prevent the animal from fully opening its jaws. The
case is curiously paralleled by the Sabre-toothed Tiger. This
species is antarctic in range. From the opposite extremity of the
globe cornes M. stefnegeri, again known by but a single skulL It
is singular on account of the large size of the brain case, and is a
native of Bering's Straits. M. hectori has its two teeth situated
quite at the extremity of the mandible, and in this feature
approximates to the genus JSerardius. It was, indeed, confounded
with that genus by one naturalist.
1 Bihanff SvensJe. Akad. Hcmdl. viii. 1883.
2 Flower, Trans. 2ooL SSoc* x. 1878, p. 415 ; and EL O., Forbes,
1893, p. 210.